​The subject of your e-mail can be one of the effective ways or the medium to communicate with your customers and grow your business. Through e-mail you can target & reach your potential customer anywhere in this world.

The right e-mail subject line can motivate the reader to click on it and read the matter. While a boring or the monotonous subject line can repel him from reading it irrespective of the amount of effort you put in designing the matter. The good subject’s line can boost your business while the loose subject line can stagnate your business, making it an important aspect in growing your business.
In a nutshell, your e-mail is worthless if the subject line is not able to convince the reader to click on it and read further.
Let me ask a general question, how you select a particular shop and its product when you are shopping in the mall? The shop owners make all efforts to motivate the visitors to buy their products by following ways:

Offering discounts to the products

Buy one and get one free

Offering discount coupons on the next purchase

Mentioning the exclusive benefits of the products and many more

Similarly, your e-mail subject line is the window for your product and you have to make it irresistible for your readers. The e-mail subject line must convince the readers to open your e-mail and read the matter. Let’s take a look at these tips for writing a good e-mail subject lines:

(1) Clarity

Your e-mail subject line must be clear enough to let your readers know what is hidden behind the subject. Or what they are about to read? The right match between the subject line and the matter increases your readership and establishes you as a sensible businessman who knows to sell the products in a right way. You will appreciate that a well defined subject line is clicked 5 times more than a loose subject line. For example I wrote on the DIY designing the solar power system, the clear subject line could be like:"Learn to design the residential solar power system by yourself?"
The above subject line is clear enough for the readers who are interested in designing the residential solar power system.

(2) Compact and precise

Although the above subject line tells clearly about the matter contained in the e-mail but if it is quite lengthy with 63 characters including the spaces. Your reader get hundreds of e-mails every day and he/she does not have time to read each and every subject line and on an average a reader spends about 2-3 seconds per subject line. You should make sure that your subject line is visible and falls straight into the eyes of the reader from starting to end in one glance. He/she does not need to move his/her eyes from left to right for reading the subject line. For that the subject line should be of optimum length of 45-55 characters including spaces.
I need to omit some of the words in the above subject line to make it short and clear. It could be like this:"Design the residential solar power system by yourself?"
Thus making it of 54 characters including spaces

Make it urgent and motivating

Although the above subject line is compact enough to fall into the eyes of the reader but is it motivating or urgent enough to let him click and read the matter contained in the subject line. The answer is probably NO. The word “yourself” in the subject “Design the residential solar power system by yourself?” is only feebly motivating which may or may not be successful in making readers to click the subject line and read the matter. You need to make it irresistible by including the element of urgency and the motivation.
The modified subject line could be like:"Design the solar power system in 3 simple steps this summer"

The words “3 simple steps” are motivating

And “this summer” is creating an urgency that one should implement before summer so as to enjoy the comfort of smooth power supply.

Personalize the subject line

One to one communication is always effective than one-to-many type of communication system. If you can design the subject line which creates a personalize effect in the mind of the readers, you win in your efforts. The use of the words “you” and “your” creates this effect in the subject line. The correct subject line could be like:"Design your solar system in 3 simple steps this summer"

​While designing the subject lines you need to think like a recipient reader and think about the subject lines which motivate you to click on it, open it and read the matter further. The subject line acts as a platform between your potential customer and product you actually want to sell. ​